Estes "HBT" tube sizes - dimensions?

[SolarYellow]

Dangit, got sent down another rabbit hole.

Due to the general unavailability of the Estes "HBT" tube sizes, I haven't worried about including them in my spreadsheet of tube sizes. But something made me curious, and I had to go digging a little. I've found records that all the sizes below exist. The convention for naming seems to be that the number is the OD in inches times 1000.

I'm fully confident in the dimensions of the HBT-1000, as they are on the Estes site now and it's the same as tubing available from several other sources.

The only other one I can find any ID or thickness cited for is HBT-1090, and I've found a range of numbers reported in various threads here and at YORF, as indicated in the table below.

All but the HBT-1475 are listed in @John Brohm's tube list, but a ring of that one is called out in the instructions for the Terrier-Sandhawk kit - possibly the only indication of its existence anywhere.

It occurs to me that the HBT-1800 may live on as BT-65 and the HBT-2000 could live on as the PSII 2-inch tube, but that's purely speculation, as I have no accurate dimensional data.

Does anyone have a catalog, samples, or other reliable information that could be used to populate the table below?

FWIW, I find measuring the thickness of a tube with calipers to be far more reliable than measuring the ID or OD, as the thickness doesn't flex out of round the way a tube does. It is, however, important to flatten out the burr or crushed/deformed material that is usually present on the edge of the tube before measuring.

Tube	ID	OD	wall TH
HBT-20
HBT-50
HBT-760
HBT-1000 heavy body tube/motor mount	0.950​	1.000​	0.025​
HBT-1090 heavy body tube Only sold stand-alone in 1998 catalog; measurements listed were for HBT-1000. Various ID measurements from TRF and YORF.	1.03 1.037 1.044	1.090​	?
HBT-1475
HBT-1800 - is this BT-65?
HBT-2000 - is this 2-inch PS II?

@Initiator001
@BEC

 

[John Brohm]

Regarding the HBT-1090 tubes, the photos below should be of help.

As you quite rightly point out, the tube bulk pack disappeared from the catalogs following the 1998 season; the nose cone pack last appeared in the 2002 catalog. The tubes in the bulk pack were/are 11.00" long and come pre-slotted for three 3/32" thick fins.

The nose cones are a little more curious. Estes provided two versions of the NC-1090 nose cones - a long one (P/N's 072630/072634/072636/072663, differentiated by color) and a short one, P/N 072626.

 

[SolarYellow]

Superb info, thanks!

I had previously been misled by the ubiquitous references to the HBT-1090 as having "1 inch ID" to thinking that was precise. With the precedent of many sizes of heavy-wall tube being 0.045 thick, I figured this was another one.

It now makes sense to me that the HBT-760 would be the same ID as BT-20, 0.710, and with 0.025 wall thickness giving it an OD of 0.760. It would be awesome if that could be confirmed.

Don't know what to guess on the remaining items.

 

[DocSeuss]

I think HBT-2000 was in the Interceptor E. I also may have that Terrier Sandhawk part. I am going to be rearranging my storage unit soon; I could try and dig up those part and measure them with a caliper for you.

 

[K'Tesh]

The BT-65 is a standard thickness cardboard tube (.0265"/1.7925" OD), whereas the HBT-1800 has definitely got a thicker wall (.036"/1.798" OD).

 

[SolarYellow]

The BT-65 is a standard thickness cardboard tube, whereas the HBT-1800 has definitely got a thicker wall.

Someone's gotta have a 2037 D-Region Tomahawk they could put calipers on.

 

[K'Tesh]

Someone's gotta have a 2037 D-Region Tomahawk they could put calipers on.

Edited previous post to include both the BT-65 and HBT-1800 thicknesses/ODs

 

[cat5752]

All but the HBT-1475 are listed in @John Brohm's tube list, but a ring of that one is called out in the instructions for the Terrier-Sandhawk kit - possibly the only indication of its existence anywhere.

Someone's gotta have a 2037 D-Region Tomahawk they could put calipers on.

I think the only place that ring was ever used was in the Terrier/Sandhawk. It allowed the Sandhawk to be locked to the Terrier, because unlike the Seahawk, the T/S could be launched as just the Sandhawk, or as the Terrier/Sandhawk. This is one of the few pictures I can find of it. I don't think it's HBT, it looks more like a large centering ring to me. Look at how thick it is. In the Instructions picture - I've circled it and added the measurements I 'think' it is, based on what it's supposed to do.

I'm trying to recreate HBT-1475 and I'm drawing a blank as well. I have a Pro Series Terrier half of the Terrier/Sandhawk, and I'm going to make a Seahawk that will separate and fly as the Terrier/SH did (instead of being glued together as the stock Seahawk is).

What measurements do you need from the DRT? Haven't even opened it, just got it a few days ago.

 

[SolarYellow]

K'Tesh posted the dimensions of the HBT-1800 in the 2037 D-Region Tomahawk airframe up above, so I think that's covered.

On the HBT-1475, the apparent convention for naming HBT tubes would indicate it has an OD of 1.475 inches (paper is always approximate), but I have no idea what the thickness would be. There's another thread discussing that ring in the Terrier-Sandhawk kit. I think the best way is to just make your own, based on the job it has to do indicated in the kit instructions and any applicable scale data.

 

[cat5752]

K'Tesh posted the dimensions of the HBT-1800 in the 2037 D-Region Tomahawk airframe up above, so I think that's covered.

On the HBT-1475, the apparent convention for naming HBT tubes would indicate it has an OD of 1.475 inches (paper is always approximate), but I have no idea what the thickness would be. There's another thread discussing that ring in the Terrier-Sandhawk kit. I think the best way is to just make your own, based on the job it has to do indicated in the kit instructions and any applicable scale data.

I edited my above post to try and make it more clear. I was pretty tired last night when I initially posted it. Something I tried this morning - the plastic transition for the Terrier booster will not quite fit in the Tomahawk body tube. The Terrier tube was used in the Python, the T/S and the Seahawk and I don't think it was used anywhere else. This is a quote I found on another page. It was a term I've never heard of.


" Unfortunately, the Python and Seahawk SM-3 fall into the category of SPEVs (Spare Parts Elimination Vehicles). The main purpose of these kits was to use up the excess of Terrier boosters (custom tubes, centering rings, fins, and in the case of the Seahawk, excess transitions) from the Terrier-Sandhawk Pro Series kit introduced in 1993."

I would gather that the Terrier/Sandhawk did not sell as well as they had hoped. I had one and it was pretty underwhelming.